Getting On Line
The Router
Even if your ISP offers you a free router there can still be a good argument for buying one from a respected manufacturer. These days you'll want wireless capability however, it's useful to have a wired connection for setup purposes and to fall back on for any troubleshooting you may need. (Lots of modern laptops no longer have a socket to allow a cable - Ethernet - connection.
We've used the term "router" here but what we're referring to is a combined router and modem, together with a wireless access point for the wireless versions. These are frequently combined now. The modem is the bit which actually does the connecting, the router allows you to connect (usually up to four) computers to the network using an Ethernet cable and the wireless access point is what allows you to connect wirelessly! Most routers will also have a built in hardware firewall which is likely to be superior to any software one.
The most popular manufacturers seem to be Netgear or D-Link but there are many others.
Follow The Instructions!
What follows is of necessity a generic instruction and those supplied by the router manufacturer and your ISP may well differ. It is important that you follow their instructions if they do differ from ours, particularly with regard to connection order.
If your router was supplied by your ISP, it will probably be set up and you won't need these instructions - just plug in and go!